Edit: My comment about thinking that I could Persist custom objects got me to thinking that I had read something about "Persistable" so I did some checking and added the portion that's in RED above--STILL get teh same errors.

Come to find out it WAS the "implements Persistable" issue--but in an effort to clean eliminate extraneous code (thinking that maybe something in a diff portion of my code was causing this), I got over-zealous and removed too much. Some of what I had removed was causing null pointers.

Now that I've restored my code and added the "implements Persistable" code, it all runs without errors.